KR102474525B1 - Method and Device for transmitting control information - Google Patents

Abstract

The present invention relates to a method for transmitting control information of a terminal, and the method of transmitting control information of a terminal according to the present invention includes the steps of receiving first control information from a base station through a first wireless communication, a channel based on the first control information Checking occupancy information; and transmitting second control information including the checked channel occupancy information to a terminal performing a second wireless communication.

Description

Method and device for transmitting control information of a terminal in a mobile communication system {Method and Device for transmitting control information}

The present invention relates to a mobile communication system, and more particularly, to check occupancy information of an unlicensed frequency channel using control information received from a base station, and to determine occupancy information of an unlicensed frequency channel for a terminal operating in an unlicensed frequency. It relates to a method and device for transmitting.

In general, mobile communication systems have been developed to provide voice services while ensuring user activity. However, mobile communication systems are gradually expanding their range to data services as well as voice, and have now developed to the extent that they can provide high-speed data services. However, in the mobile communication system currently providing services, a more advanced mobile communication system is required due to a shortage of resources and users' demand for higher-speed services.

On the other hand, in the data service, unlike the voice service, resources to be allocated are determined according to the amount of data to be transmitted and channel conditions. Therefore, in a wireless communication system such as a mobile communication system, a scheduler performs management such as allocating transmission resources in consideration of the amount of resources to be transmitted, channel conditions, and amount of data. This is also performed in long-term evolution (LTE), one of the next-generation mobile communication systems, and a scheduler located in a base station manages and allocates radio transmission resources.

In addition, recently, a licensed assisted access (LAA) system utilizing a licensed band and an unlicensed band has emerged to increase spectral efficiency.

Since the LTE communication system is a system using a licensed frequency band, a frequency owner can exclusively use frequency resources in a desired manner. However, since a communication device using an unlicensed frequency band must share and use a frequency channel with other communication devices, a method for coexisting without collision in the unlicensed frequency band is required. As the method, a listen before talk (LBT) method is used, which refers to a method of determining whether a selected frequency channel is currently not in use and transmitting a communication signal. At this time, an operation of checking whether another communication device is using the selected frequency channel may be referred to as a channel sensing operation or a clear channel assessment (CCA) operation.

Meanwhile, in the case of an LAA terminal capable of LAA communication in the LAA system, control information may be received from a base station to check channel occupancy information including channel occupancy status and channel occupancy time of an unlicensed frequency band. However, there is a problem in that other terminals (eg, LAA terminals or WLAN terminals that cannot decode the control information) cannot check channel occupancy information using control information transmitted from the base station. Therefore, when there is a terminal that is not included in the service range of the LAA base station but performs WiFi communication around the LAA terminal, a problem in which LAA communication is interrupted due to the neighboring WiFi terminal may occur (Hidden Node Problem).

The present invention has been proposed to solve the above problems, and an object of the present invention is a method for a terminal to receive control information, check channel occupancy information, and transmit the channel occupancy information to another terminal operating in an unlicensed frequency, and suggest a device.

A method for transmitting control information of a terminal of the present invention for solving the above problems includes receiving first control information from a base station through a first wireless communication, checking channel occupancy information based on the first control information and transmitting second control information including the checked channel occupancy information to a terminal performing second wireless communication.

In addition, in the terminal of the present invention for solving the above problems, a first module for performing a first wireless communication; A second module for performing a second wireless communication; Receives first control information from a base station through the first module, checks channel occupation information based on the first control information, and transmits second control information including the checked channel occupation information through the second module. It characterized in that it comprises a control unit for transmitting to the terminal performing the second wireless communication.

According to the present invention, a terminal operating in an unlicensed frequency band can efficiently operate by transmitting channel occupancy information to a terminal operating in an unlicensed frequency band.

1 is a diagram showing the structure of an LTE system to which the present invention is applied.
2 is a diagram showing a radio protocol structure in an LTE system to which the present invention is applied.
3 is a diagram for explaining carrier aggregation in a terminal.
4 is a diagram illustrating an unlicensed frequency channel.
5 is a diagram illustrating a process of checking channel occupancy in the LAA system according to the present invention.
6A is a diagram showing a network configuration diagram according to the present invention.
6B is a flowchart illustrating a method of transmitting control information of a terminal according to an embodiment of the present invention.
7 is a flowchart illustrating a process of transmitting control information by a terminal according to an embodiment of the present invention.
8A is a diagram illustrating an LTE channel and frame structure in an LTE system.
8B is a diagram illustrating control information transmitted in units of subframes.
9 is a diagram illustrating a frame structure of second control information including channel occupancy time.
10 is a diagram illustrating a method of transmitting second control information by a terminal according to an embodiment of the present invention.
11 is a diagram illustrating another method of transmitting second control information by a terminal according to an embodiment of the present invention.
12 is a flowchart illustrating a process of transmitting control information by a terminal according to another embodiment of the present invention.
13 is a diagram illustrating a method of transmitting second control information by a terminal according to another embodiment of the present invention.
14 is a diagram showing the configuration of a terminal according to the present invention.
15 is a diagram showing another configuration of a terminal according to the present invention.
16 is a diagram showing another configuration of a terminal according to the present invention.
17 is a diagram showing the configuration of a terminal including a first communication module and a second communication module according to the present invention.
18 is a diagram showing the configuration of a WLAN communication module according to the present invention.
19 is a diagram showing the configuration of a LAA communication module according to the present invention.
20 is a diagram showing the configuration of a management module according to the present invention.
21 is a diagram showing the configuration of a base station according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In describing the embodiments, descriptions of technical contents that are well known in the technical field to which the present invention pertains and are not directly related to the present invention will be omitted. This is to more clearly convey the gist of the present invention without obscuring it by omitting unnecessary description.

For the same reason, in the accompanying drawings, some components are exaggerated, omitted, or schematically illustrated. Also, the size of each component does not entirely reflect the actual size. In each figure, the same reference number is assigned to the same or corresponding component.

In describing the embodiments in this specification, descriptions of technical contents that are well known in the technical field to which the present invention pertains and are not directly related to the present invention will be omitted. This is to more clearly convey the gist of the present invention without obscuring it by omitting unnecessary description.

For the same reason, in the accompanying drawings, some components are exaggerated, omitted, or schematically illustrated. Also, the size of each component does not entirely reflect the actual size. In each figure, the same reference number is assigned to the same or corresponding component.

Advantages and features of the present invention, and methods for achieving them, will become clear with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only the present embodiments make the disclosure of the present invention complete, and common knowledge in the art to which the present invention belongs It is provided to fully inform the holder of the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numbers designate like elements throughout the specification.

At this time, it will be understood that each block of the process flow chart diagrams and combinations of the flow chart diagrams can be performed by computer program instructions. These computer program instructions may be embodied in a processor of a general purpose computer, special purpose computer, or other programmable data processing equipment, so that the instructions executed by the processor of the computer or other programmable data processing equipment are described in the flowchart block(s). It creates means to perform functions. These computer program instructions may also be stored in a computer usable or computer readable memory that can be directed to a computer or other programmable data processing equipment to implement functionality in a particular way, such that the computer usable or computer readable memory The instructions stored in are also capable of producing an article of manufacture containing instruction means that perform the functions described in the flowchart block(s). The computer program instructions can also be loaded on a computer or other programmable data processing equipment, so that a series of operational steps are performed on the computer or other programmable data processing equipment to create a computer-executed process to generate computer or other programmable data processing equipment. Instructions for performing processing equipment may also provide steps for performing the functions described in the flowchart block(s).

Additionally, each block may represent a module, segment, or portion of code that includes one or more executable instructions for executing specified logical function(s). It should also be noted that in some alternative implementations it is possible for the functions mentioned in the blocks to occur out of order. For example, two blocks shown in succession may in fact be executed substantially concurrently, or the blocks may sometimes be executed in reverse order depending on their function.

At this time, the term '~unit' used in this embodiment means software or a hardware component such as FPGA or ASIC, and '~unit' performs certain roles. However, '~ part' is not limited to software or hardware. '~bu' may be configured to be in an addressable storage medium and may be configured to reproduce one or more processors. Therefore, as an example, '~unit' refers to components such as software components, object-oriented software components, class components, and task components, processes, functions, properties, and procedures. , subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. Functions provided within components and '~units' may be combined into smaller numbers of components and '~units' or further separated into additional components and '~units'. In addition, components and '~units' may be implemented to play one or more CPUs in a device or a secure multimedia card.

1 is a diagram showing the structure of an LTE system to which the present invention is applied.

Referring to FIG. 1, as shown, the radio access network of the LTE system includes an evolved node B (ENB, Node B or base station) 105, 110, 115, and 120 and a mobility management entity (MME 125). and S-GW (130, serving-gateway). Terminal 135 accesses an external network through ENBs 105 to 120 and S-GW 130.

In FIG. 1, ENBs 105 to 120 correspond to existing Node Bs of the UMTS system. The ENB is connected to the UE 135 through a radio channel and performs a more complex role than the existing Node B. In the LTE system, since all user traffic, including real-time services such as VoIP (Voice over IP) through the Internet protocol, is serviced through a shared channel, status information such as buffer status, available transmission power status, and channel status of UEs A device that collects and schedules is required, and ENBs (105 to 120) are in charge of this. One ENB usually controls multiple cells. For example, in order to implement a transmission rate of 100 Mbps, the LTE system uses orthogonal frequency division multiplexing (hereinafter referred to as OFDM) as a radio access technology in a 20 MHz bandwidth, for example. In addition, an adaptive modulation & coding (AMC) method for determining a modulation scheme and a channel coding rate according to the channel condition of the terminal is applied. The S-GW 130 is a device that provides a data bearer and creates or removes a data bearer under the control of the MME 125 . The MME is a device in charge of various control functions as well as a mobility management function for a terminal, and is connected to a plurality of base stations.

2 is a diagram showing a radio protocol structure in an LTE system to which the present invention is applied.

Referring to FIG. 2, the radio protocol of the LTE system consists of PDCP (Packet Data Convergence Protocol 205 and 240), RLC (Radio Link Control 210 and 235), and MAC (Medium Access Control 215 and 230) in the terminal and ENB, respectively. Packet Data Convergence Protocol (PDCP) 205, 240 is in charge of operations such as IP header compression/restoration, and radio link control (Radio Link Control, hereinafter referred to as RLC) 210, 235 is a PDCP PDU (Packet Data Unit) ) to an appropriate size. The MACs 215 and 230 are connected to several RLC layer devices configured in one terminal, and perform operations of multiplexing RLC PDUs to MAC PDUs and demultiplexing RLC PDUs from MAC PDUs. The physical layers 220 and 225 channel-code and modulate higher-layer data, make OFDM symbols and transmit them through a radio channel, or demodulate and channel-decode OFDM symbols received through a radio channel and transmit them to higher layers. . Also, in the physical layer, HARQ (Hybrid ARQ) is used for additional error correction, and the receiving end transmits whether or not the packet transmitted by the transmitting end has been received with 1 bit. This is referred to as HARQ ACK/NACK information. Downlink HARQ ACK/NACK information for uplink transmission is transmitted through Physical Hybrid-ARQ Indicator Channel (PHICH) physical channel, and uplink HARQ ACK/NACK information for downlink transmission is transmitted through Physical Uplink Control Channel (PUCCH) or PUSCH (Physical Uplink Shared Channel) It can be transmitted through a physical channel.

3 is a diagram for explaining carrier aggregation in a terminal.

Referring to FIG. 3, one base station generally transmits and receives multiple carriers over several frequency bands. For example, when a carrier 315 having a center frequency of f1 and a carrier having a center frequency of f3 310 are transmitted from the base station 305, conventionally, one terminal uses one of the two carriers to transmit data. has been sent and received. However, a terminal having carrier aggregation capability can simultaneously transmit and receive data from multiple carriers.

On the other hand, in the case of the LAA system, the base station can transmit and receive data with the terminal by integrating the carrier wave of the licensed frequency band and the carrier wave of the unlicensed frequency band transmitted from the base station. Accordingly, a terminal having carrier aggregation capability can simultaneously transmit and receive data from a carrier of a licensed frequency band and a carrier of an unlicensed frequency band. In this way, frequency aggregation is performed using the carriers of the licensed frequency band and the carriers of the unlicensed frequency band, thereby increasing the efficiency of data transmission.

4 is a diagram illustrating an unlicensed frequency channel.

Currently, the 5 GHz band is allocated for unlicensed use with a bandwidth of about 500 MHz in several countries. Referring to FIG. 4 , a total of 25 carriers 410 having a bandwidth 400 of 20 MHz constitute a bandwidth of 500 MHz. Considering that the LTE communication system can combine up to 32 carriers in the current licensed band, when CA is performed including the unlicensed band, more wideband frequency resources can be used.

5 is a diagram illustrating a process of checking channel occupancy in the LAA system according to the present invention.

Since the LTE communication system is a system using a licensed frequency band, a frequency owner can exclusively use frequency resources in a desired method. However, since a communication device using an unlicensed frequency must share and use a frequency channel with other communication devices, it is necessary to check whether the corresponding frequency channel is occupied. A process of determining whether another communication device is using a corresponding frequency channel may be referred to as CCA or channel sensing.

Referring to FIG. 5 , a graph illustrating a process in which a base station or a terminal determines whether an unlicensed frequency channel is occupied and transmits data using an unlicensed frequency is shown. The base station or terminal may perform CCA in the CCA interval 511 to check whether the unlicensed frequency is occupied. At this time, the base station or the terminal may perform CCA for more than a predetermined time (eg, 20 μs).

In the present invention, as an example, it is assumed that a terminal checks whether or not an unlicensed frequency is occupied. The terminal may measure the energy level of the unlicensed frequency channel to determine whether the unlicensed frequency is occupied. Accordingly, when the energy level of the channel is less than a predetermined value, the terminal may determine that the unlicensed band is not occupied and transmit data in the unlicensed band (513). At this time, the time at which the base station or the terminal transmits data may be referred to as channel occupation time 516 .

In addition, when the UE performs CCA once, it can occupy the unlicensed band for a minimum of 1 ms to a maximum of 10 ms, and thereafter, it does not perform transmission for at least 5% of the channel occupancy time 516 and enters an idle state 514. Must keep. This is referred to as an idle section (517).

On the other hand, if the magnitude of energy is greater than or equal to a certain value, the terminal can decode the control information received from the base station to determine whether the unlicensed frequency is occupied and the channel occupation time.

The terminal can check the channel occupation time using the control information received from the LTE base station. At this time, the control information received from the LTE base station may be transmitted through a control channel (eg, physical downlink control channel (PDCCH)). However, only a specific terminal can decode control information received through the PDCCH, and only a terminal to which radio resources are allocated at a corresponding time can check channel occupancy information using the control information.

6A is a diagram showing a network configuration diagram according to the present invention.

Referring to FIG. 6A , a network according to the present invention may include a base station 601 , a first terminal 603 , and a second terminal 605 . In the present invention, the base station 601 may mean an LTE base station or a LAA base station. In this embodiment, the first terminal 603 is a LAA terminal capable of operating in licensed and unlicensed frequencies, and the second terminal 603 is a WLAN terminal capable of operating in unlicensed frequencies. ) is described as an example. At this time, the WLAN communication may include a wireless communication subsystem or WiFi radio for using a WLAN protocol, and the WLAN protocol is IEEE 802.11 technology (eg, IEEE 802.11a; IEEE 802.11b; IEEE 802.11g; IEEE 802.11 -2007; IEEE 802.11n; IEEE 802.11-2012; IEEE 802.11ac). However, embodiments of the present invention are not limited to the above examples. For example, the present invention can be applied even when both the first terminal 603 and the second terminal 605 are LAA terminals.

The base station 601 may transmit first control information to the first terminal 603 in step S610.

When the base station 601 transmits a data packet using an unlicensed frequency (hereinafter, transmission of a data packet by the base station using an unlicensed frequency may be referred to as LAA transmission), since the unlicensed frequency is occupied, the packet Terminals other than the terminal receiving the (first terminal and second terminal in the present invention) cannot transmit and receive data through the corresponding unlicensed frequency.

Accordingly, the base station 601 may include information related to LAA transmission in the first control information and transmit it to the first terminal in step S610. At this time, the information related to LAA transmission may mean channel occupancy information of an unlicensed frequency band, and may be referred to as channel occupancy information hereinafter.

Upon receiving the first control information, the first terminal may check channel occupancy information of an unlicensed frequency using the first control information.

However, since only a specific terminal (the first terminal in the present invention) can decode the first control information transmitted from the base station as described above, only the first terminal to which radio resources are allocated at that time can use the control information to obtain channel occupancy information. can be checked, and the second terminal cannot check the channel occupancy information. In this case, the second terminal may include a WLAN terminal capable of performing WLAN communication in an unlicensed frequency band. Alternatively, the second terminal may mean a LAA terminal capable of performing communication in an unlicensed frequency band.

Accordingly, the first terminal may generate second control information based on the first control information in step S620. Specifically, the first terminal may include channel occupancy information checked based on the first control information in the second control information.

And, the first terminal that generated the second control information may transmit the second control information generated in step S630 to the second terminal.

The second control information may refer to control information transmitted through WLAN communication or a WLAN protocol, and may include, for example, a CTS packet. Accordingly, the first terminal may transmit the second control information to the second terminal through the WLAN protocol.

Accordingly, the WLAN terminal or the LAA terminal may receive the second control information through the WLAN protocol.

Upon receiving the second control information, the second terminal may check the channel occupation time using the channel occupation information included in the second control information, and may not perform a data transmission process through the channel. The WLAN terminal receiving the second control information knows that the channel will be occupied during the period and performs subsequent operations. The subsequent operation is defined in WLAN communication. In another embodiment, during the identified channel occupancy time, the WLAN terminal may stop the channel sensing operation.

6B is a flowchart illustrating a method of transmitting control information of a terminal according to an embodiment of the present invention.

Referring to FIG. 6B , the base station may transmit first control information to the first terminal in step S640. The first control information may include scheduling information that is resource allocation information allocated by the base station to the terminal to transmit downlink data. Alternatively, the first control information may include scheduling information that is resource allocation information allocated by the base station to receive uplink data. In the present invention, resource allocation information and scheduling information are used interchangeably. After checking the first control information, the first terminal can check a resource to transmit downlink data or a resource to transmit uplink data.

In addition, when transmitting a packet to another terminal through an unlicensed frequency band, the base station may include channel occupancy information of the unlicensed frequency band in the first control information.

Upon receiving the first control information, the first terminal may check channel occupancy information based on the first control information in step S650. Therefore, the terminal can check channel occupancy information including channel occupancy time, which is the time at which the base station transmits a packet through the unlicensed frequency band.

After confirming the channel occupancy information, the first terminal may generate second control information including the channel occupancy information in order to transmit the channel occupancy information to another terminal in step S660.

The second control information may include control information transmitted through a WLAN protocol, and may mean, for example, an RTS packet or a CTS packet. Accordingly, the first terminal may generate an RTS packet or a CTS packet including channel occupancy information in a specific field. However, the present invention is not limited thereto.

Thereafter, the first terminal may transmit the second control information to the second terminal in step S670. At this time, the first terminal may transmit second control information to the second terminal through the WLAN protocol. The second terminal of the present invention may include at least one terminal performing communication through an unlicensed frequency band, and at least one or more second terminals may receive the second control information and check channel occupancy information.

The second terminal that has checked the channel occupancy information using the second control information may stop data transmission during the channel occupancy time. Additionally, a channel sensing operation for data transmission may be stopped.

7 is a flowchart illustrating a process of transmitting control information by a terminal according to an embodiment of the present invention.

Referring to FIG. 7 , the terminal may access (camping on) a cell of the base station (hereinafter, referred to as an LAA cell) in step S710.

The LAA system performs a frequency aggregation technique using licensed and unlicensed frequencies to increase frequency efficiency and downlink performance, and the LAA cell can be used as a secondary cell (SCell). That is, the UE may configure the LAA cell as the SCell.

A specific process for the terminal to access (camping on) the LAA cell is as follows.

A UE accessing a primary cell (PCell) may transmit UE capability to the PCell. The terminal information may include a combination of frequency bands in which the terminal is capable of frequency aggregation (eg, a CA combination). In this case, a combination of frequency bands capable of frequency aggregation may include a combination of frequency bands used to perform LAA (eg, a combination of LAA). Accordingly, the PCell that has received the terminal information can select a SCell that can be supported by the PCell from the combination of the frequency bands, and can transmit information on the selected SCell to the terminal. At this time, the information of the selected SCell may include a combination of frequency bands used to perform LAA (eg, LAA combination). Accordingly, the terminal receiving the SCell information can additionally camp on the SCell while maintaining a camp on state for the corresponding PCell by using the SCell information.

Meanwhile, the SCell information may include SCell frequency information, and the SCell information may be expressed as shown in Table 1, for example.

[Table 1]

A terminal that has set the LAA cell as the SCell can change the setting of the WLAN module of the terminal using the frequency information of the SCell. The terminal may convert frequency information of the SCell into frequency information of the WLAN system, and may change settings of the WLAN module so that the WLAN module operates in the converted frequency information.

For example, when the LAA module and the WLAN module included in the terminal use one antenna, the antenna may be set to the frequency of the LAA cell to access the LAA cell. In this case, the terminal separately uses a WLAN module There is no need to change the settings of Meanwhile, when the LAA module and the WLAN module of the terminal use separate antennas, the terminal may adjust the frequency setting of the antenna used by the WLAN module according to the frequency information of the LAA cell (SCell). As another example, the terminal may configure the front-end of the WLAN module according to the frequency information of the LAA cell. As another example, when there is data to be transmitted through the WLAN module, the terminal may set the antenna and front-end of the WLAN module regardless of the frequency information of the LAA cell.

As another embodiment, a process of checking a transmission rate of a channel corresponding to the frequency information through a WLAN module may be included. The transmission speed of the confirmed channel may be used as information for calculating a time point for transmitting a CTS packet or an RTS packet through the WLAN module.

Thereafter, the terminal may receive first control information from the base station in step S720. When there is data to be transmitted to the terminal, the base station may transmit first control information to the terminal through the PCell or the SCell. At this time, the base station may include channel occupancy information in the first control information.

As a method for the base station to transmit the first control information including the channel occupancy time information of the unlicensed frequency, the following three methods may be considered.

First, channel occupancy information for the SCell may be included in control information for the PCell and transmitted through the PCell. Second, control information about Scell including channel occupancy information of unlicensed frequencies can be transmitted through PCell (cross carrier scheduling method in LTE). Thirdly, the base station may include channel occupancy information of an unlicensed frequency in control information for the SCell and transmit the same through the SCell.

In addition, the first control information may include resource allocation information allocated to transmit downlink data. That is, the first control information may mean scheduling information and downlink control information (DCI). When the first control information is DCI, the base station may include the channel occupancy information in the DCI using a specific field included in a predefined DCI format. Alternatively, the base station may newly define a separate field capable of indicating the channel occupancy information in a predefined DCI format and include the channel occupancy information in the DCI.

The terminal may receive the first control information through a control channel, a data channel, or a separate channel, and details are described with reference to FIG. 8A.

8A is a diagram illustrating an LTE channel and frame structure in an LTE system. One radio frame 811 consists of 10 subframes. In addition, one subframe 812 may have a length of 1 ms and consist of two slots (slot 0 and slot 1). At this time, the control channel is located at the head of one subframe on the time axis. Referring to FIG. 8A , reference number 813 indicates a region in which a PDCCH, which is a type of control channel, can be located. The control channel signal may be transmitted over L OFDM symbols located at the head of the subframe.

In the present invention, the base station may generate first control information and transmit it through a PDCCH region. Also, in the ePDCCH, control information can be transmitted through a data channel region. Accordingly, the base station may transmit control information through the data channel. Alternatively, the base station may transmit control information through a physical broadcast channel (PBCH) located in the data channel region. Alternatively, the base station may transmit control information using a separate channel defined to transmit the channel occupancy time. In the present invention, a case where a base station transmits control information through a PDCCH region will be described as an example.

Returning to the description of FIG. 7 , the terminal receiving the first control information can check the channel occupancy information included in the first control information in step S730.

The first control information may include information related to resources through which the base station transmits data to the designated first terminal. Alternatively, the first control information may include a time at which downlink transmission and/or uplink transmission using an unlicensed frequency is performed in a corresponding region. Alternatively, the first control information may include information obtained by integrating occupancy information of unlicensed frequencies for all terminals at that time.

Therefore, in step S730, the 1st terminal provides resource allocation information for the 1st terminal, information that integrates information on occupancy of unlicensed frequencies for all terminals at that time, or information related to the time at which transmission is performed using unlicensed frequencies in the corresponding area. At least one of them can be identified.

In addition, the first control information may be transmitted in units of subframes, and the first terminal uses the first control information as well as resource allocation information in a subframe in which the first control information is received, as well as information on subsequent subframes. It may include resource allocation information in a subframe. Details are described in FIG. 8B.

8B is a diagram illustrating control information transmitted in units of subframes.

Referring to FIG. 8B, one radio frame 821 may include 10 subframes 822, 823, and 824, and one subframe may include two slots 825. Also, one slot may include 6 or 7 OFDM symbols. The base station may transmit first control information through a PDCCH included in a subframe, and the first control information may include resource allocation information of a corresponding subframe allocated to each terminal.

Also, the first control information may include resource allocation information in a plurality of subframes. For example, when the first control information is received through the PDCCH included in subframe 1 822, the first control information includes resource allocation information allocated to the terminal among resources included in subframe 1 822. can In addition, the first control information may include resource allocation information in subframe 2 823 and/or subframe 3 824 as well as resource allocation information in subframe 1 822 .

Alternatively, the first control information may include resource allocation information for subframes after the subframe in which the first control information is transmitted. For example, when the first control information is received through the PDCCH included in subframe 1 822, the first control information includes resource allocation information for subframe 2 823 instead of subframe 1 822. may be included.

On the other hand, when the base station transmits control information through the PDCCH, only the designated terminal can decode the control information to check the channel occupancy information. That is, in the present invention, only the first terminal to which radio resources are allocated to the base station at the time when the base station transmits the first control information can check the control information.

Therefore, a terminal to which radio resources are not allocated at the time when the base station transmits the control information cannot check the control information and cannot check the channel occupancy information.

As another embodiment, the control information may be received and interpreted by all LAA terminals including the LAA module or the LTE module. At this time, a new radio network temporary identifier (RNTI), LAA-RNTI, may be defined so that all LAA terminals including the LAA module or the LTE module can receive and decode control information.

Specifically, the base station may generate control information using the LAA-RNTI, and may transmit the control information by positioning it in a common search space of the PDCCH. Therefore, a terminal capable of LAA communication can decode control information and check channel occupancy information using the LAA-RNTI.

However, even when control information is generated using the LAA-RNTI, the WLAN terminal cannot check the channel occupancy information.

Therefore, the terminal that has confirmed the channel occupation information based on the first control information can generate second control information including the channel occupation information in step S740 and transmit the second control information to the second terminal.

The second control information may mean information to be transmitted to a terminal that communicates through an unlicensed frequency band, and a CTS packet will be described as an example in the present invention. However, it is not limited to the second control information CTS packet of the present invention, and may include various types of packets transmitted through the WLAN protocol including RTS packets or data packets.

Specifically, in the process of generating the second control information, the terminal may generate a CTS packet including channel occupancy information in a specific field. The structure of the second control information will be described in detail with reference to FIG. 9 .

9 is a diagram illustrating a frame structure of second control information including channel occupancy time.

Referring to FIG. 9 , the second control information may include a duration field. The first terminal may receive the first control information, include the confirmed channel occupancy time in the duration field 960, and generate second control information including the duration field 960. In addition, the first terminal may transmit the generated second control information to the second terminal. Therefore, the second terminal receiving the packet can check the channel occupation time using the information included in the duration field 960 included in the second control information.

Returning to the description of FIG. 7 , the first terminal that has generated the second control information may transmit the second control information to the second terminal in step S750. The first terminal may determine a transmission start time of the second control information in consideration of a transmission required time and a delay time according to the size of the second control information, and transmit the second control information at the transmission start time. The specific details are as follows.

Scheduling information included in the first control information may include frequency information for downlink transmission in a subframe, data transmission start time information, data transmission end time information, or data transmission maintenance time information.

For example, the first control information may include data transmission start time information (eg, 200us after receiving the first control information) and data transmission duration information (eg, 100us). Alternatively, the first control information may include a start time of data transmission (eg, 200us after receiving the first control information) and an end time of data transmission (eg, 300us after receiving the control information). Therefore, the first terminal can determine the transmission duration time of data, that is, the channel occupation time (100us) using the data transmission start time and data transmission end time included in the first control information.

When the channel occupation time is 100us, the first terminal may generate second control information including the channel occupation time 100us.

In addition, the first terminal subtracts an expected time required for transmitting the second control information (CTS packet in this embodiment) (hereinafter, it may be referred to as an expected CTS transmission time) and a delay time from the data transmission start time. A transmission start time of the second control information may be determined. That is, the first terminal may calculate the transmission start time of the second control information using 200us-(expected CTS transmission time + SIFS).

At this time, the expected CTS transmission time may vary according to channel conditions. In a WLAN system, CTS can be defined to be transmitted in 14 bytes. At this time, since the CTS transmission rate is changed according to the channel state, the expected CTS transmission time may be changed. For example, it can be expected that the time taken to transmit the CTS will take from 4.67us for 24Mbps to 112us for 1Mbps, depending on network conditions. The channel state is measured in the WLAN module of the terminal, and the terminal can determine the time required to transmit the CTS using the measured channel information. In addition, the terminal may transmit the estimated time required for CTS transmission measured by the WLAN module to the management module.

Alternatively, the first terminal may be configured to transmit the CTS at a preset rate. For example, when CTS is set to be transmitted at 12 Mbps, the expected CTS transmission time for transmitting a 14 byte CTS packet may be 9.34 us.

In addition, the delay time (delay(≒SIFS)) can be calculated in correspondence with the SIFS of the WLAN system. In the WLAN system, the SIFS value may vary according to the version of the 802.11 standard, and the corresponding information is shown in Table 2 below.

[Table 2]

Accordingly, when the CTS is configured to transmit at 12Mbps and the SIFS is 16us, the first terminal may transmit second control information 200-(9.34+16)us after receiving the first control information.

As another embodiment, the management module of the first terminal may adjust the delay time according to the LAA system. If the data transmission start time after receiving the first control information is less than (CTS transmission time + SIFS), it is also possible to adjust the delay value and set it to be smaller than SIFS.

Meanwhile, when it is determined that the data transmission start time included in the first control information is smaller than the expected CTS transmission time, that is, when the CTS packet cannot be transmitted before data is received, the first terminal is in a state in which the CTS cannot be transmitted. and may not transmit the CTS packet.

Upon receiving the second control information, the second terminal may stop the channel sensing operation during the channel occupation time included in the second control information.

Meanwhile, although the CTS packet has been described as an example in the present invention, the first terminal may include channel occupancy information in an RTS packet or data packet and transmit the same to the second terminal. Alternatively, the first terminal may generate another type of control information including channel occupancy information and transmit it to the second terminal. Alternatively, the first terminal may transmit channel occupancy information to other terminals by broadcasting.

10 is a diagram illustrating a method for a terminal to transmit second control information according to an embodiment of the present invention.

In the present invention, a CTS packet is described as the second information, but the content of the present invention is not limited thereto.

Referring to FIG. 10 , the LAA cell may transmit (1001) first control information to the terminal. The first control information may include channel occupancy information. In addition, the first control information may include information such as data transmission start time 1002, data transmission maintenance time 1003, and data transmission completion time 1003 after receiving the first control information.

The first terminal may determine a transmission start time of the second control information using the information. Specifically, the first terminal may determine the transmission start time of the second control information by subtracting the time taken to transmit the CTS packet and the delay time from the data transmission start time 1002 .

For example, it is assumed that the data transmission start point 1002 is 200 us and the transmission rate of the second control information is set to 12 Mbps. The data transmission start time 1002 may refer to a time required to transmit data after receiving the first control information, and may be the same as the data transmission waiting time 1007 .

In addition, when the CTS packet is set to be transmitted at 12 Mbps, it is assumed that the time required to transmit the second control information (1005) is 9.34 us, and the delay time (1006) is 16 us according to Table 2.

Therefore, the transmission start time of the second control information can be calculated as 200 - (9.34 + 16), and the terminal can transmit the second control information including the channel occupancy information 174.66us after receiving the first control information. .

11 is a diagram illustrating another method of transmitting second control information by a terminal according to an embodiment of the present invention.

11 illustrates a second control information transmission method when the first control information includes resource allocation information for a subframe subsequent to the subframe in which the first control information is received.

Referring to FIG. 11 , the LAA cell may transmit (1101) first control information to the terminal. The first control information may include channel occupancy information. In addition, the first control information includes information such as data transmission start time 1103, data transmission maintenance time 1104, and data transmission completion time 1105 in subframes after the subframe in which the first control information is received. may be included. Accordingly, the first control information may also include a scheduling delay 1102 from receiving the first control information to a subframe.

The first terminal may determine a transmission start time of the second control information by using information included in the first control information. Specifically, the first terminal may determine the transmission start time of the second control information by subtracting the time required to transmit the CTS packet and the delay time from the data transmission start time 1102 .

For example, it is assumed that the data transmission start point 1103 is 200 us and the transmission rate of the second control information is set to 12 Mbps. The data transmission start time 1103 may mean a time required from the scheduling delay time 1102 to data transmission.

Therefore, when the CTS packet is set to be transmitted at 12Mbps, assuming that the time required to transmit the second control information (1106) is 9.34us and the delay time (1107) is 16us according to Table 2, 2 The transmission start time of control information may be a time obtained by adding 200-(9.34+16) us to the scheduling delay time.

Accordingly, the terminal may transmit second control information including channel occupancy information at a time when 174.66us is added to the scheduling delay time after receiving the first control information.

12 is a flowchart illustrating a process of transmitting control information by a terminal according to another embodiment of the present invention.

FIG. 12 describes a method for receiving control information including resource allocation information for transmitting uplink data, checking channel occupancy information in the control information, and transmitting the same to another terminal, when the terminal transmits uplink data. do.

Referring to FIG. 12 , the terminal may access (camping on) the LAA cell in step S1210.

The LAA system performs a frequency aggregation technique using licensed and unlicensed frequencies to increase frequency efficiency and downlink performance, and the LAA cell can be used as a secondary cell (SCell). That is, the UE may configure the LAA cell as the SCell.

A specific process for the terminal to access (camping on) the LAA cell is as follows.

A UE accessing a primary cell (PCell) may transmit UE capability to the PCell. The UE information may include a combination (CA combination) of frequency bands in which the UE is capable of frequency aggregation. In this case, a combination of frequency bands capable of frequency aggregation may include a combination of frequency bands used to perform LAA (LAA combination). Accordingly, the PCell that has received the terminal information can select a SCell that can be supported by the PCell from the combination of the frequency bands, and can transmit information on the selected SCell to the terminal. Accordingly, the terminal receiving the SCell information can additionally camp on the SCell while maintaining a camp on state for the corresponding PCell by using the SCell information.

Meanwhile, the SCell information may include SCell frequency information, and the SCell information may be expressed as shown in Table 1.

A terminal that has set the LAA cell as the SCell can change the setting of the WLAN module of the terminal using the frequency information of the SCell. The terminal may convert frequency information of the SCell into frequency information of the WLAN system, and may change settings of the WLAN module so that the WLAN module operates in the converted frequency information.

For example, when the LAA module and the WLAN module included in the terminal use one antenna, the antenna may be set to the frequency of the LAA cell to access the LAA cell. In this case, the terminal separately uses a WLAN module There is no need to change the settings of Meanwhile, when the LAA module and the WLAN module of the terminal use separate antennas, the terminal may adjust the frequency setting of the antenna used by the WLAN module according to the frequency information of the LAA cell. As another example, the terminal may configure the front-end of the WLAN module according to the frequency information of the LAA cell. As another example, when there is data to be transmitted through the WLAN module, the terminal may set the antenna and front-end of the WLAN module regardless of the frequency information of the LAA cell.

Thereafter, when there is data to be transmitted to the base station, the terminal may request allocation of uplink resources for uplink data transmission in step S1220.

Upon receiving the uplink resource allocation request, the base station may transmit first control information including uplink scheduling information to the terminal according to the request in step S1230. In this case, the first control information may mean downlink control information (DCI) including uplink scheduling information. When the first control information is DCI, the base station may include the channel occupancy information in the DCI using a specific field included in a predefined DCI format. Alternatively, the base station may newly define a separate field capable of indicating the channel occupancy time in a predefined DCI format and include the channel occupancy information in the DCI.

The terminal may receive the first control information through a control channel, a data channel, or a separate channel, and in the present invention, a case of receiving the first control information through a PDCCH will be described as an example.

Upon receiving the first control information, the terminal may check the channel occupancy information included in the first control information in step S1240.

The first control information may include information related to resources for transmitting data from the designated first terminal to the base station. Alternatively, the first control information may include a time at which downlink transmission and/or uplink transmission using an unlicensed frequency is performed in a corresponding region. Alternatively, the first control information may include information obtained by integrating occupancy information of unlicensed frequencies for all terminals at that time.

Therefore, as a result of checking the channel occupancy information, the first terminal performs transmission using uplink resource allocation information for the first terminal, information combining unlicensed frequency occupancy information for all terminals at that time, or using an unlicensed frequency in the corresponding area. At least one of the pieces of information related to the time being used may be checked.

In addition, the first control information may be transmitted in units of subframes, and includes, for example, scheduling information for a subframe 4 ms (four subframes) after the subframe in which the first control information is received. can do. Accordingly, UE 1 may transmit data in a subframe to which scheduling information is allocated.

Alternatively, the first control information may include scheduling information for at least one subframe. When the first control information includes scheduling information for a plurality of subframes, the first terminal may check usable subframes through LBT. And, the first terminal may transmit data to the base station in an usable subframe. When an available subframe is confirmed through LBT, the second control information may be transmitted to the second or third terminal before data is transmitted to the base station.

Meanwhile, when the base station transmits control information through the PDCCH, only the designated terminal can decode the control information and check the channel occupancy information. That is, in the present invention, only the first terminal to which radio resources are allocated to the base station at the time when the base station transmits the first control information can check the control information.

Therefore, a terminal to which radio resources are not allocated at the time when the base station transmits the control information cannot check the control information and cannot check the channel occupancy information.

As another embodiment, the control information may be received and interpreted by all LAA terminals including the LAA module or the LTE module. At this time, a new radio network temporary identifier (RNTI), LAA-RNTI, may be defined so that all LAA terminals including the LAA module or the LTE module can receive and decode control information.

Specifically, the base station can generate control information using the LAA-RNTI, and the terminal can decode the control information and check the channel occupancy information using the LAA-RNTI.

However, even when control information is generated using the LAA-RNTI, the WLAN terminal cannot check the channel occupancy information.

Accordingly, the first terminal confirming the channel occupation information may generate second control information including the channel occupation information in step S1250 and transmit the second control information to the second terminal.

The second control information may mean information to be transmitted to a terminal that communicates through an unlicensed frequency band, and a CTS packet will be described as an example in the present invention. However, it is not limited to the second control information CTS packet of the present invention, and may include various types of packets transmitted through the WLAN protocol including RTS packets or data packets.

The first terminal that generated the second control information may transmit the second control information generated in step S1260 to the second terminal. The first terminal may determine a transmission start time of the second control information according to scheduling information included in the first control information, and transmit the second control information at the transmission start time. The specific details are as follows.

In addition, the scheduling information included in the first control information includes frequency information for uplink transmission, data transmission start time information, data transmission end time information, or data transmission maintenance time information in a subframe allocated for data transmission. can be included

For example, the first control information includes subframe information to transmit data, data transmission start time information (eg, 200us after the start of the subframe to transmit data), and data transmission end time (eg, data transmission end time). At least one of data transmission holding time information (eg, 100 us) may be included.

In this case, the subframe to transmit data may include a subframe in which the first control information is received, or may include a subframe after a predetermined subframe in the subframe in which the first control information is received.

In addition, when the first control information includes the data transmission start time and data transmission end time, the first terminal uses the data transmission start time and data transmission end time included in the first control information to maintain data transmission time. , that is, the channel occupancy time (100us) can be determined.

When the channel occupation time is 100us, the first terminal may generate second control information including the channel occupation time 100us.

In addition, the first terminal subtracts an expected time required for transmitting the second control information (CTS packet in this embodiment) (hereinafter, it may be referred to as an expected CTS transmission time) and a delay time from the data transmission start time. A transmission start time of the second control information may be determined. If the subframe to transmit data is a subframe after 4 ms, the first terminal can calculate the transmission start time of the second control information using 4 ms + 200 us - (CTS transmission expected time + SIFS).

At this time, the expected CTS transmission time may vary according to channel conditions. That is, the size of the CTS is 14 bytes, and since the CTS transmission rate changes according to the channel state, the expected CTS transmission time may change. For example, it can be expected that the time taken to transmit the CTS will take from 4.67us for 24Mbps to 112us for 1Mbps, depending on network conditions. The channel state is measured in the WLAN module of the terminal, and the terminal can determine the time required to transmit the CTS using the measured channel information.

Alternatively, the first terminal may be configured to transmit the CTS at a preset rate. For example, when CTS is set to be transmitted at 12 Mbps, the expected CTS transmission time for transmitting a 14 byte CTS packet may be 9.34 us.

In addition, the delay time (delay(≒SIFS)) can be calculated in correspondence with the SIFS of the WLAN system. In the WLAN system, the SIFS value may vary according to the version of the 802.11 standard, and the corresponding information is shown in Table 2.

Therefore, if the CTS is set to transmit at 12Mbps and the SIFS is 16us based on 802.11ac, the first terminal can transmit the second control information after 4ms + 200us - (9.34 + 16)us after receiving the first control information .

As another embodiment, the management module of the first terminal may adjust the delay time according to the LAA system. If the data transmission start time after receiving the first control information is less than (CTS transmission time + SIFS), it is also possible to adjust the delay value and set it to be smaller than SIFS.

Meanwhile, when it is determined that the data transmission start time included in the first control information is smaller than the expected CTS transmission time, that is, when the CTS cannot be transmitted before data is received, the first terminal determines that the CTS cannot be transmitted. and may not transmit CTS.

Upon receiving the second control information, the second terminal may stop the channel sensing operation during the channel occupation time included in the second control information.

Meanwhile, although the CTS packet has been described as an example in the present invention, the first terminal may include channel occupancy information in an RTS packet or data packet and transmit the same to the second terminal. Alternatively, the first terminal may generate another type of control information including channel occupancy information and transmit it to the second terminal. Alternatively, the first terminal may transmit channel occupancy information to other terminals by broadcasting.

13 is a diagram illustrating a method of transmitting second control information by a terminal according to another embodiment of the present invention.

Referring to FIG. 13 , the LAA cell may transmit first control information to the terminal (1301). The first control information may include channel occupancy information. In addition, the first control information may include information such as data transmission start time 1303, data transmission maintenance time 1303, and data transmission completion time 1303. As described above, information such as the data transmission start time 1303, the data transmission sustain time 1303, and the data transmission completion time 1303 may be information in a subframe in which the first control information is received, , or may be information in a subframe after a predetermined subframe in the subframe in which the first control information is received.

However, when the first control information is information in a subframe following a predetermined subframe in the received subframe, the first control information may include an uplink delay time 1302.

The first terminal may determine a transmission start point of the second control information by using the information. Specifically, the first terminal may determine the transmission start time of the second control information by subtracting the time taken to transmit the CTS and the delay time from the data transmission start time 1303 .

For example, it is assumed that the data transmission start point 1303 is 200 us and the transmission rate of the second control information is set to 12 Mbps. The data transmission start time 1303 may mean the time required from the UL delay time 1302 to data transmission.

When the CTS packet is set to be transmitted at 12Mbps, assuming that the time required to transmit the second control information (1306) is 9.34us and the delay time (1307) is 16us according to Table 2, the second control information The information transmission start time may be a time obtained by adding 200 - (9.34 + 16) us to the uplink delay time.

Accordingly, the terminal may transmit second control information including channel occupancy information at a time when 174.66us is added to the uplink delay time after receiving the first control information.

14 is a diagram showing the configuration of a terminal according to the present invention.

Referring to FIG. 14 , the terminal of the present invention may include a management module 1410, a WLAN communication module 1420, and a LAA communication module 1430. 14 is a diagram illustrating a case where a management module 1410, a WLAN communication module 1420, and a LAA communication module 1430 are included in one chipset. At this time, the WLAN communication module 1120 and the LAA communication module 1130 may be connected through a universal asynchronous receiver/transmitter (UART), a serial peripheral interface (SPI), or PCI express (PCIE).

The WLAN communication module 1420 may receive control information through wireless communication with a WLAN AP or WLAN Station. The WLAN communication module 1420 may receive control information such as RTS packets and CTS packets. In addition, the WLAN communication module 1420 may check a channel state and transmit channel state information to the management module 1410 . Also, the WLAN communication module 1420 may receive control information (eg, a CTS packet) generated by the management module from the management module and transmit it to another terminal.

The LAA communication module 1430 may receive first control information through wireless communication with the base station. The LAA communication module 1430 may check the channel occupancy information by decoding the first control information using the wireless identifier.

Alternatively, the LAA communication module 1430 may decode the first control information using the newly defined parameter, the LAA radio identifier. The LAA radio identifier may be defined for all LAA terminals, and when the base station scrambles the first control information using the LAA radio identifier, all LAA terminals capable of communicating with the base station may receive and decode the first control information. have. Accordingly, the LAA communication module 1430 may check the channel occupancy information using the first control information and transmit the channel occupancy information to the management module 1410 . In addition, the LAA communication module 1430 may decode the first control information and transmit other information confirmed to the management module 1410 .

Alternatively, the LAA communication module 1430 may transmit the received first control information to the management module 1410, and the management module 1410 may decode the first control information to check the channel occupancy information.

The management module 1410 may share information obtained from the WLAN communication module 1420 and the LAA communication module 1430, or may control operations of the WLAN communication module 1420 and the LAA communication module 1430.

In addition, the management module 1410 may generate second control information to be transmitted through the WLAN protocol using channel occupancy information obtained from the LAA communication module 1430 . For example, the management module 1410 may generate a CTS packet including channel occupancy information.

In addition, the management module 1410 may transfer the generated second control information to another terminal through the WLAN communication module 1420 . The management module 1410 may determine a transmission start time of the second control information using scheduling information included in the first control information received through the LAA communication module, and transmit the second control information to another terminal at the determined transmission start time. can be sent to Specifically, the management module 1410 may transmit the second control information to another terminal at a time obtained by subtracting the time required to transmit the second control information and the delay time from the data transmission start time.

Also, the management module 1410 may control the operation of the WLAN communication module 1420 and the LAA communication module 1430. Specifically, upon receiving channel occupancy information from the LAA communication module 1430, the management module 1410 may control the operation of the WLAN communication module based on the channel occupancy time included in the channel occupancy information.

In addition, the management module 1410 may transmit an uplink resource allocation request to the base station through the LAA communication module 1430 when there is uplink data to be transmitted to the base station.

In addition, when the control information received through the LAA communication module 1430 includes uplink scheduling information for a plurality of subframes, the management module 1410 selects a subframe to be used for transmitting data by performing an LBT operation. can decide

15 is a diagram showing another configuration of a terminal according to the present invention.

Referring to FIG. 15 , the terminal of the present invention may include a management module 1510, a WLAN communication module 1520, and a LAA communication module 1520. 15 is a diagram illustrating a case where the management module 1510, the WLAN communication module 1520, and the LAA communication module 1530 are included in different chipsets. At this time, the WLAN communication module 1520 and the LAA communication module 1530 may be connected through UART, SPI, PCIE, or the like.

The WLAN communication module 1520 may receive control information through wireless communication with a WLAN AP or WLAN Station. The WLAN communication module 1520 may receive control information such as RTS packets and CTS packets. In addition, the WLAN communication module 1520 may receive control information (eg, CTS packet) generated by the management module from the management module and transmit it to another terminal.

At this time, since the WLAN communication module 1520 and the management module 1510 are included in different chipsets, a protocol for communication between the WLAN communication module and the management module may be defined, and control information, etc. this can be transmitted.

The LAA communication module 1530 may receive first control information through wireless communication with the base station. The LAA communication module 1530 may check the channel occupancy information by decoding the first control information using the wireless identifier.

Alternatively, the LAA communication module 1430 may decode the first control information using the newly defined parameter, the LAA radio identifier. The LAA radio identifier may be defined for all LAA terminals, and when the base station scrambles the first control information using the LAA radio identifier, all LAA terminals capable of communicating with the base station may receive and decode the first control information. have. Accordingly, the LAA communication module 1530 may check channel occupation information using the first control information and transmit the channel occupation information to the management module 1510 . Since the LAA communication module 1530 and the management module 1510 are included in different chipsets, a protocol for communication between the LAA communication module and the management module may be defined.

Alternatively, the LAA communication module 1530 may transmit the received first control information to the management module 1510, and the management module 1510 may decode the first control information to check the channel occupancy information.

The management module 1510 may share information obtained from the WLAN communication module 1520 and the LAA communication module 1530, or may control operations of the WLAN communication module 1520 and the LAA communication module 1530. At this time, the management module 1510 may share information between the WLAN communication module and the LAA communication module using a defined protocol, and control the operation of the WLAN communication module 1520 and the LAA communication module 1230. can

In addition, the management module 1510 may generate second control information to be transmitted through the WLAN protocol using channel occupancy information obtained from the LAA communication module 1530 . For example, the management module 1510 may generate a CTS packet including channel occupancy.

In addition, the management module 1510 may transfer the generated second control information to another terminal through the WLAN communication module 1520. The management module 1510 may determine a transmission start time of the second control information using scheduling information included in the first control information received through the LAA communication module, and transmit the second control information to another terminal at the determined transmission start time. can be sent to Specifically, the management module 1510 may transmit the second control information to another terminal at a time obtained by subtracting the time required to transmit the second control information and the delay time from the data transmission start time.

Also, the management module 1510 may control the operation of the WLAN communication module 1520 and the LAA communication module 1530. Specifically, upon receiving channel occupancy information from the LAA communication module 1530, the management module 1510 may control the operation of the WLAN communication module based on the channel occupancy time included in the channel occupancy information. That is, the management module 1510 may transmit channel occupancy information received through the LAA communication module to neighboring WLAN terminals through the WLAN communication module. The WLAN terminal receiving the second control information knows that the channel will be occupied during the period and performs subsequent operations. Subsequent operations are defined in WLAN communication. In addition, when there is uplink data to be transmitted to the base station, the management module 1510 may transmit an uplink resource allocation request to the base station through the LAA communication module 1530. have.

In addition, when the control information received through the LAA communication module 1430 includes uplink scheduling information for a plurality of subframes, the management module 1510 selects a subframe to be used for transmitting data by performing an LBT operation. can decide

16 is a diagram showing another configuration of a terminal according to the present invention.

Referring to FIG. 16 , the terminal of the present invention may include a WLAN communication module 1620 and a LAA communication module 1640. 16 is a diagram illustrating a case in which the WLAN communication module 1620 and the LAA communication module 1640 are included in different chipsets, and each chipset includes a management module.

The WLAN communication module 1620 may receive control information through wireless communication with a WLAN AP or WLAN Station. The WLAN communication module 1620 may receive control information such as RTS packets and CTS packets. In addition, the WLAN communication module 1320 may receive second control information (eg, CTS packet) generated from the management module 1610 included in the same chipset and transmit it to another terminal.

The LAA communication module 1640 may receive first control information through wireless communication with the base station. The LAA communication module 1640 may check the channel occupation time by decoding the first control information using the wireless identifier.

Alternatively, the LAA communication module 1640 may decode the first control information using the newly defined parameter, the LAA radio identifier. The LAA radio identifier may be defined for all LAA terminals, and when the base station scrambles the first control information using the LAA radio identifier, all LAA terminals capable of communicating with the base station may receive and decode the first control information. have. Accordingly, the LAA communication module 1640 may check the channel occupancy information and transmit the channel occupancy information to the management module 1630 included in the same chipset.

Alternatively, the LAA communication module 1640 may transmit the received first control information to the management module 1630 included in the same chipset, and the management module 1630 may decode the first control information to check the channel occupancy information have.

The management module 1610 and the management module 1630 share information obtained from the WLAN communication module 1620 and the LAA communication module 1640, or control the operation of the WLAN communication module 1620 and the LAA communication module 1640. can do.

The management module 1610 or the management module 1630 may generate second control information to be transmitted through the WLAN protocol using the acquired channel occupancy information. Specifically, the management module 1630 may generate second control information including channel occupancy information received from the LAA communication module 1640 or directly confirmed, and transmit the second control information to the management module 1610 . Alternatively, the management module 1610 may receive channel occupation information included in the first control information from the management module 1630 and generate second control information including the channel occupation information. At this time, the management module 1610 and the management module 1630 may generate a CTS packet including channel occupancy information in a specific field.

In addition, the management module 1610 may transmit the second control information directly generated or received from the management module 1630 to another terminal through the WLAN communication module 1620 .

At this time, the management module 1610 may determine the transmission start time of the second control information using scheduling information included in the first control information received through the LAA communication module, and the second control information at the determined transmission start time. can be transmitted to other terminals. Specifically, the management module 1410 may transmit the second control information to another terminal at a time obtained by subtracting the time required to transmit the second control information and the delay time from the data transmission start time.

Alternatively, the transmission start time of the second control information may be determined by the management module 1630 and transmitted to the management module 1610 .

Alternatively, the communication module of the WLAN 1620 may directly determine the transmission start time of the second control information and transmit the second control information to another terminal at the transmission start time.

Details of calculating the transmission start time of the second control information are the same as described above, and will be omitted below.

Also, the management module 1610 may control the operation of the WLAN communication module 1620. Specifically, upon receiving channel occupancy information from the LAA communication module 1640, the management module 1610 may control the operation of the WLAN communication module based on the channel occupancy time included in the channel occupancy information. That is, the management module 1610 may turn off the power of the WLAN communication module, turn on the power saving mode, or turn off the channel sensing function.

In addition, the management module 1630 may transmit an uplink resource allocation request to the base station through the LAA communication module 1640 when there is uplink data to be transmitted to the base station.

In addition, when the control information received through the LAA communication module 1640 includes uplink scheduling information for a plurality of subframes, the management module 1630 selects a subframe to be used for transmitting data by performing an LBT operation. can decide

Also, in the present invention, a chipset including a WLAN communication module and a chipset including a LAA communication module may not include a management module. That is, the control unit of the WLAN communication module and the control unit of the LAA communication module may serve as a management module.

17 is a diagram showing the configuration of a terminal including a first communication module and a second communication module according to the present invention.

Referring to FIG. 17 , the terminal of the present invention may include a communication unit 1710, a control unit 1720, and a storage unit 1730. In this embodiment, a case in which the first communication module and the second communication module are included in the communication unit 1710 will be described as an example. However, the first communication module and the second communication module may be included in the control unit. Also, in this embodiment, a case in which the first communication module is a WLAN communication module and the second communication module is a LAA communication module will be described as an example. In addition, the WLAN communication module and the LAA communication module may be included in a control unit or a communication unit in the form described in FIGS. 14 to 16 .

The communication unit 1710 may communicate with other network entities. The communication unit 1710 may receive first control information from the base station using the second communication module. Also, the communication unit 1710 may receive a radio identifier required to decode the first control information. Also, the communication unit 1710 may transmit the second control information generated by the control unit 1720 to another terminal.

The controller 1720 may control to receive first control information from the base station by using the first communication module. In addition, the controller 1720 may decode the received control information to check channel occupancy information of unlicensed frequencies. In this case, the first control information may be decoded using the wireless identifier received by the terminal or stored in the terminal. Alternatively, the controller 1720 may decode the control information using a wireless identifier commonly defined for all terminals.

In addition, the controller 1720 may generate second control information including the checked channel occupancy information and transmit it to another terminal using a WLAN protocol. Also, the controller 1720 may control the operation of the second communication module using the checked channel occupancy information.

Also, the controller 1720 may determine a transmission start time of the second control information by using scheduling information included in the first control information.

Also, when there is uplink data to be transmitted to the base station, the controller 1720 may transmit an uplink resource allocation request to the base station through the first communication module.

In addition, when the received first control information includes uplink scheduling information for a plurality of subframes, the controller 1720 may perform an LBT operation to determine a subframe to be used for transmitting data.

The storage unit 1730 may store a radio identifier for decoding control information. Also, the storage unit 1430 may store the checked channel occupancy information and the generated second control information.

18 is a diagram showing the configuration of a WLAN communication module according to the present invention.

According to the present invention, the WLAN module may be composed of a communication unit 1810, a control unit 1820, and a storage unit 1830.

The communication unit 1810 may communicate with other network entities. The communication unit 1810 may receive control information through wireless communication with a WLAN AP or WLAN station. Also, the communication unit 1810 may receive second control information from the management module.

The controller 1820 may measure the channel state and check information for determining an expected time required for transmission of the second control information. In addition, the controller 1820 may control to transmit the generated second control information to another terminal. In addition, the controller 1820 may control to determine a transmission start time of the second control information according to scheduling information included in the first control information.

The storage unit 1830 may store the second control information received from the management module.

19 is a diagram showing the configuration of a LAA communication module according to the present invention.

According to the present invention, the LAA communication module may be composed of a communication unit 1910, a control unit 1920, and a storage unit 1930.

The communication unit 1910 may communicate with other network entities. The communication unit 1910 may receive control information through wireless communication with the base station. Also, the communication unit 1910 may transmit an uplink resource allocation request to the base station.

The controller 1920 may check channel occupancy information of an unlicensed frequency using the received control information. The controller 1920 may check channel occupancy information using control information received through a subframe included in a control channel, a data channel, or a separate channel. Specifically, the controller 1920 may decode the received control information using a wireless identifier to check channel occupancy information. Alternatively, the control unit 1920 may decode control information and check channel occupancy information using the LAA radio identifier defined for all terminals. In addition, the controller 1920 may control transmission of channel occupancy information including the channel occupancy time to the management module.

The storage unit 1930 may store a radio identifier for decoding control information. Also, the storage unit 1930 may store channel occupancy information obtained from control information.

20 is a diagram showing the configuration of a management module according to the present invention.

According to the present invention, the management module may be composed of a communication unit 2010, a control unit 2020, and a storage unit 2030.

The communication unit 2010 may communicate with other network entities. The communication unit 2010 may receive channel occupancy information from the LAA communication module. Also, the communication unit 2010 may transmit second control information to the WLAN communication module.

The control unit 2020 may check the channel occupation time using the channel occupation information received from the LAA communication module. In addition, the control unit 2020 may generate second control information including the confirmed channel occupancy information. The control unit 2020 may control the generated second control information to be transmitted to another terminal through the WLAN communication module.

The control unit 2020 may determine a transmission start time of the second control information based on scheduling information included in the first control information received from the base station, and may transmit the second control information at the transmission start time.

In addition, the control unit 2020 may control the operation of the WLAN module according to the channel occupancy information.

The storage unit 2030 may store channel occupancy information received from the LAA communication module.

21 is a diagram showing the configuration of a base station according to the present invention.

Referring to FIG. 21 , the base station of the present invention may include a communication unit 2110, a control unit 2120, and a storage unit 2130.

The communication unit 2110 may communicate with other network entities. The communication unit 2110 may transmit the generated control information to the terminal and may receive data from the terminal.

The control unit 2120 may check scheduling information allocated to terminals capable of using the LAA and determine an integrated channel occupation time for all terminals. Also, the controller 2120 may generate control information using the channel occupation time and the wireless identifier. Specifically, the control unit 2120 may generate control information obtained by combining a CRC with downlink transmission information including a channel occupation time and scrambling the CRC using a radio identifier. In addition, the control unit 2020 may transmit the generated control information to the terminal.

Alternatively, the control unit 2120 may generate control information using LAA radio identifiers defined for all terminals. The control unit 2120 may generate control information obtained by combining the CRC with downlink transmission information including the channel occupation time and scrambling the CRC using the LAA-radio identifier. In addition, the control unit 2020 may transmit the generated control information to the terminal. As such, when using the LAA-radio identifier, all LAA terminals can decode control information to check channel occupancy information. At this time, the control unit 2020 may transmit information related to LAA-radio identifier information used to generate control information to the terminal.

The storage unit 2030 may store information related to the LAA-wireless identifier. Also, the storage unit 2030 may store scheduling information for each terminal.

On the other hand, preferred embodiments of the present invention have been disclosed in the present specification and drawings, and although specific terms have been used, they are only used in a general sense to easily explain the technical content of the present invention and help understanding of the present invention. It is not intended to limit the scope of the invention. It is obvious to those skilled in the art that other modified examples based on the technical idea of the present invention can be implemented in addition to the embodiments disclosed herein.

Claims (12)

A method for transmitting control information of a terminal in a mobile communication system,
Receiving first control information from a base station through first wireless communication;
Checking channel occupancy information based on the first control information; and
Transmitting second control information including the confirmed channel occupancy information to a terminal performing second wireless communication,
Receiving the first control information,
A method comprising receiving downlink control information (DCI) including channel occupancy information through a physical downlink control channel (PDCCH).
According to claim 1,
The second control information,
A method comprising a clear to send (CTS) packet including channel occupancy information. According to claim 1,
Transmitting the second control information,
determining a transmission start time of the second control information based on the first control information; and
And transmitting the second control information at the transmission start time. According to claim 1,
Transmitting the second control information,
The method further comprising transmitting the second control information to a terminal performing the second wireless communication through a WLAN protocol. delete According to claim 1,
Wherein the first wireless communication comprises an LTE communication and the second wireless communication comprises a WLAN communication. In the terminal for receiving control information,
A first module for performing a first wireless communication;
A second module for performing a second wireless communication;
Receives first control information from a base station through the first module, checks channel occupation information based on the first control information, and transmits second control information including the checked channel occupation information through the second module. And a control unit for transmitting to the terminal performing the second wireless communication,
The first control information,
A terminal characterized in that it includes downlink control information (DCI) including channel occupancy information through a physical downlink control channel (PDCCH).
According to claim 7,
The second control information,
A terminal comprising a clear to send (CTS) packet including channel occupancy information. According to claim 7,
The control unit,
The terminal further comprising determining a transmission start time of the second control information based on the first control information, and transmitting the second control information at the transmission start time. According to claim 7,
The control unit,
The terminal further comprising transmitting the second control information to a terminal performing the second wireless communication through a WLAN protocol.
delete According to claim 7,
Wherein the first wireless communication includes LTE communication, and the second wireless communication includes WLAN communication.

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